Python Program:

Example:

num=int(input("Enter your number : "))
sum = 0
while num!=0 :
  sum+=num%10
  num=int(num/10)
print("Sum of total number of digits : ",sum)

Output:

  Enter Your number : 1132
  Sum of total number of digits : 7

Main Logic :

while num!=0 :
  sum+=num%10    #Find single digits, & add them
  num=int(num/10)